Ex-Wallabies boss labels Top League as 'unrecognisable' on eve of competition's final edition

Japan's Top League will look to put a year lost to the COVID-19 pandemic behind it on Saturday when play returns for the final season in the competition's current guise.

Bolstered by the arrival of a string of high-profile foreign players, the league will also hope it is not too late to tap into the positive energy from the successful hosting of the Rugby World Cup in 2019.

Saturday's start comes more than a month after the original commencement date of Jan. 16, with the league postponed due to a series of COVID-19 outbreaks among multiple teams.

Fans will see a host of top-class talent spread across the competition's 16 teams as they battle towards the Top League final in Tokyo on May 23.

Several members of South Africa's 2019 World Cup winning side will grace the stage, as will Australia captain Michael Hooper and All Blacks stars Beauden Barrett and Kieran Read.

Former Crusaders coach Robbie Deans, who has been at the helm of the Panasonic Wild Knights since 2014, said the standard in Japan was improving all the time.

"It's very good and it's getting better and better," he told AAP. "From when I arrived up here, it's unrecognisable."

The format for the 2021 campaign will see teams split into two groups of eight before they are joined by four teams from the Top Challenge League – the country's second division - for the knockout rounds.

The new season will be the last to feature corporation-led teams as Japan looks to turn the set-up into a more professional competition in 2022.

The new league will be expanded to 25 teams across three divisions, as nine sides from the Top Challenge League join their Top League counterparts.

A shake-up of the domestic game was first mooted after the 2019 Rugby World Cup, when hosts Japan reached the quarter-finals for the first time.

Further calls were made for change when the Sunwolves, Japan's sole representative club in the Super Rugby competition, were disbanded last year, giving rise to fears that Japanese players would not get exposure to the game at the top level.